1. Field of the Invention
The present invention is related to an actuation device. More particularly, the present invention is related to an explosive activated spring actuated device.
2. State of the Art
In the discussion of the state of the art that follows, reference is made to certain structures and/or methods. However, the following references should not be construed as an admission that these structures and/or methods constitute prior art. Applicant expressly reserves the right to demonstrate that such structures and/or methods: do not qualify as prior art against the present invention.
Certain actuation devices in use today, such as pin pullers, use a piston housed in a cylinder which is pressurized by a pyrotechnic charge. The pyrotechnic charge is detonated by an electrical current or other means. The resulting gas pressure forces the piston and an integral pin or shaft associated with it to move over a predetermined distance. The piston and pin or shaft are unique to the particular device application.
Conventional devices having the above-mentioned construction, and their associated methods, pose certain problems and disadvantages.
First, devices of the above-described construction are one-time use or xe2x80x9cone-shotxe2x80x9ddevices.
Second, the use of the pyrotechnic force for activation and actuation of the device presents certain difficulties.
Use of the pyrotechnic charge for actuation results in ballistic shock impact forces that must be taken into account in the design of the device. For instance, the housing and the pin of such devices must be designed with sufficient strength to withstand the forces created upon detonation of the pyrotechnic charge.
Also, since the explosive gas pressure created by the pyrotechnic charge dissipates immediately after actuation, a means of preventing xe2x80x9cbounce-backxe2x80x9d of the actuated pin is required. Typically, such devices are provided with a mechanism for locking the pin in its actuated position. The requirement of providing such mechanisms further complicates the design.
Moreover, choosing the proper size of the pyrotechnic charge is not a simple task. Generally, the charge must be large enough to effectively actuate the piston and its integral pin or shaft, but cannot be so large that it causes problems such as excessive xe2x80x9cbounce-backxe2x80x9d, or fracture, of the pin.
The design of such devices is even more difficult when the pin or shaft to be actuated is relatively heavy. In attempting to design such a device for actuation of a relatively heavy pin it has been found that conventional practices for sizing the pyrotechnic charge and dealing with the ballistics of the device are inadequate to lock the pin, and thereby prevent bounce back.
Thus, there is a need for an improved actuation device, and associated method, which are both reliable and economical.
According to the present invention, device and method are provided which overcome the disadvantages set forth above, and others.
According to one aspect, the present invention provides a pin puller device comprising: a housing; a non-pyrotechnic actuation mechanism disposed within the housing; a release mechanism constructed to initiate the release of the actuation mechanism in response to an activation signal; and a pin or shaft member operatively associated with the actuation mechanism.
According to a further aspect, the present invention provides a method of actuating a pin or shaft, the method comprising: providing a housing; providing a non-pyrotechnic actuation device within the housing; providing a release mechanism; providing a pin or shaft operatively associated with the actuation mechanism; transmitting an activation signal to the release mechanism; releasing the actuation mechanism; and actuating the pin or shaft.